# PyTEA-O: a Python implementation of Two-Entropies Analysis for protein sequence variation analysis

## TL;DR

PyTEA-O is a Python tool for analyzing protein sequence variation, helping identify key residues that influence protein function.

## Contribution

PyTEA-O introduces an accessible and flexible implementation of Two-Entropies Analysis with intuitive visualizations and physicochemical scoring.

## Key findings

- PyTEA-O identifies residues modulating protein function through MSA analysis.
- A case study on OTUD7B reveals a crucial position affecting substrate affinity.
- The tool supports small MSAs and provides customizable visualizations.

## Abstract

Protein sequence variation analysis is a topic of broad interest in drug discovery and protein engineering to support modulation of protein function for diverse biotechnological and therapeutic applications. To assist in the analysis of multiple sequence alignments (MSAs) and identify residues that account for protein function specificity, computational tools have been developed. Yet, existing programs often omit consideration of amino acid properties, flexibility beyond fixed webserver interfaces, accessible source code, or compatibility with small MSAs.

To address these limitations, we present PyTEA-O, a Python implementation of Two-Entropies Analysis that has been developed to be easy to use for the analysis of protein sequence variation. To help users analyze the MSA and screen for residues of interest, we generate modifiable and intuitive visualizations. These visualizations, together with a scoring approach for identifying alignment positions with (dis-)similar physicochemical properties, presents a powerful tool for sequence variability analysis. To demonstrate its capabilities, we present a case study based on the deubiquitinase OTUD7B (Cezanne) where we identify a crucial position that modulates its affinity for its substrate.

PyTEA-O is available at https://github.com/CDDLeiden/PyTEA-O/ and archived via Zenodo (https://doi.org/10.5281/zenodo.15914598).